The saving-savvy folks at The Consumerist blog have put together a template Excel spreadsheet for managing personal finances. It's the kind of thing you always say you're going to do, but they went ahead and did it for you, and it's free.
It's not a new thing, but Consumerist's budget spreadsheet has come back, after being lost to the vagaries of server maintenance. The site has instructions on setting it up, including tips on thinking through your monthly expenses and advice on how much you should plan on socking away for a rainy day, retirement and other expenses.
Download Our Free Easy Excel Budget Spreadsheet [The Consumerist]